This application is for a Program Project for broadly based research in statistical and quantitative genetics. The program will support research of personnel in the Departments of Statistics, Genetics and Crop Science at North Carolina State University. Consortium arrangements are proposed with the University of California at Davis, the University of California at Riverside, Dalhousie University, and the University of Minnesota. Theoretical research will be concerned with statistical aspects of using molecular genetic data to construct evolutionary histories, and in determining the effects of mutation on quantitative characters. Methods for constructing evolutionary trees will be applied to some chloroplast DNA sequences from a range of plant species. Quantitative genetic studies in Drosophila will focus on the effects of transposable element induced mutation on bristle numbers. Work on mice will consider the quantitative genetic aspects of developmental change in cranofacial structure. Restriction to recombination as a possible isolating mechanism for the evolutionary divergence of races of maize and teosinte will be studied using isozyme marker stocks. Both isozyme and RFLP markers will be employed in searches for genes affecting components of yield in maize.